That must be it, the sound of running water always makes me run to the bathroom. You can change your white noise to a train or Meadow, those ought to be safe. Unless the train makes you wake up thinking that we are all being rounded up.
These posts about night sounds reminded me of something funny - years ago son’s friend’s mother decided to take a group of boys (including my son) camping, hiking and ziplining. She is a city-girl, not outdoorsy, and had never been camping in her life.
When they were all settling in at night she put on cricket noises so it would sound like they were outside. The boys were like, “We ARE outside, and you can actually hear crickets”